cmd/compile: avoid closure for captured dynamic constant #5370
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NeedsInvestigation
Someone must examine and confirm this is a valid issue and not a duplicate of an existing one.
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You have not shown us a complete program. The correct compilation here depends on what g
does with f.
If I add func g(func()) with no body, then in the absence of information the compiler
allocates a closure, correctly.
If I add func g(func()) {}, then since the argument does not escape, the compiler makes
a function on the stack, again correctly.
So I think this is working.
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I do not believe the body of g is important for demonstration purposes.
Put another way, the compiler should recognize that the program is equivalent to the
following
func f() {
println("")
}
func main() {
g(f)
}
and avoid emitting code to allocate a closure either on the stack or on the heap.
Instead, the compiler should arrange to have f point to a non-closure function similar
to what I have shown above.
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The compiler is not very smart about compiling away closures. The following function needlessly allocates a closure at runtime func main() { s := "" f := func () { println(s) } g(f) } This example should succumb to closure analysis. The closure should be eliminated at compile time and replaced by an ordinary function.The text was updated successfully, but these errors were encountered: